Propeller for steamships



J. CHRISTOFF.

PROPELLER FOR'ST EAMSHIPS. APPLICATION FILED SEPT. 10, l9l9.

1,372,402, Patented Mar. 22, 19211 UNITED STATES PATENT OFFICE.

301mm GHRISTOIEF, on nrsour, lancxnmvn; N W ZEAL ND.

PnornLLEn ron. srnansmrs.

object of providing improved means for use" in the propulsion of steam or other power driven ships, and it consists in a special form of propeller and, manner of actuating it, by which a greater propulsive force is obtained than is obtained by the use of the ordinary rotating screw propeller.

According hereto the propeller 1s] formed by a number of bladesthat are hinged or knuckled to a suitable head that iscarried on the outer end of a shaft extending horizontally through the ships stern and to which a longitudinal reciprocating motion is imparted by the vessels engines. motion is designed, and the blades are so mounted, that on their outward travel relatively to the ships stern, they will open out to assume a position at right angles to the line of their shaft, and on their inward travel they will turn in to lines parallel with the shaft. Consequently, therefore on their outward movement they will present the full area of their faces to the water thus obtaining a rearward pushthereon that will send the ship forward, and on their inward movement will present their edges to the line of travel thereby presenting a minimum of resistance to the water.

Any desired number of propellers, thus constructed and operated may be arranged upon the stern of the ship. For most purposes however, a convenient arrangement is to employ two propellers, arranged one on each side of the ships rudder and working in alternation to balance the driving power, or in unison with one another if so desired. Such an arrangement as applied to two bladed propellers is shown in the accompanying drawings, illustrating the invention.

These drawings are mainly of diagrammatic form to show the general features governing the construction and operation of the propellers. These features in thelr details of construction may be'varied in quite a number of ways to suit different circum- This V Specification of LettersTatent. Patent fl 22,192 Appli cation flled September 10; 1919. Serial no. 22,958.

stances,and it is to be understood that the invention is not confined to such details of construction as are shown in the drawings. Referring tothedrawings:- l 9 Figure 1 is aside elevation, the ships stern beingindicated by dotted. lines.

Fig. 2 a plan of the propulsive means.

Fig. 3 is a detail inner face view of one of the propellers.

Fig. 4 is a" rearjelevation of an alternaso that the two blades extend vertically on therespective sides of such head. The two blades are therefore capable of turning to l lieparallel with one another, or to turn outward to extend in the same plane. In each position they engage stops formed on the head that keep them from folding right in together and also keep them from turning out beyond the line in which they occupy the same plane.

The head B is supported to slide upon a guide bar D fixed to extend from the ships stern. This baris shown as arranged to extend rearward from a suitable stufiing box fitting E arranged on such stern. Passing through the said stuffing box are a pair of sliding rods F that together form the propeller shaft and at their outer ends, are fixed to the head B and at their inner ends, inside the ship, are attached to a slide head G carried in horizontal guides H and adapted to be moved reciprocally in such guides by means of a connecting rod J and crank K mounted on a shaft M that receives rotation from the ships engines. By these means, the head B is moved reciprocally along the guide bar D, the blades A-A opening outward on the rearward movement of the head ward and exerting its propulsive force, the

I otheris moving idlyforward. This will balance the driving shaft in its rotation. The same principle of construction and operation may be adapted to a propeller formed withjmore than two blades such blades in such'a case being disposed to extend radially from the head B and being hinged or knuckled at their inner ends to such head so as to be capable of turning in to liein planes parallel with the shaft or of turning out to I extend in planes at right angles with such shaft. Such a construction as applied to a three bladed propeller is shown in Fig. it.

The angles at which the propellers work maybe varied if so"clesired, for instance they v operate independently of one another in orderto assistin the steering or maneuverin ofthe vessel.

- 1. In combination, a guide shaft, a head mountedfor longitudinal movement on the guide shaft rods attached to the head and mounted for rcciprocatory movement parallel with the guide shaft, and blades hinged to the head.

2; In combination, a guide shaft, a head mounted for longitudinal movement on the guide shaft, blades hinged to the head, rods attached to the head and arranged for reciprocatory movement parallel with the guide shaft, a crosshead connecting said rods, guides for the crosshead, a crank shaft, and a rod connecting the crank of said shaft with the crosshead.

3. In combination, a pair of guide shafts, a head mounted on each guide shaft for longitudinal movement, blades hinged to each head, rods attached to each head, crosshcads, for the rods, guides for the crossheads, a shaft having cranks arranged in angular rclation, means to operate said crank shaft, and rods connecting the cranks of said shaft to the crossheads.

In testimony whereof, I have signed this speclficatlon 1n the presence of two subscrib- W. E. HUGHES, J.'E. CLUATT. 

